<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>selector group</title>

    <style type="text/css">

        body {
            color: red;
        }

        h1, h2 {
            color: green;
        }

        p {
            color: blue;
        }

    </style>
</head>
<body>


    <h1>header1</h1>
    <h2>header2</h2>
    <h3>header3</h3>
    <p>A</p>


</body>
</html>